This MDCRC is organized around the central theme of improving muscle regeneration in a number of types of muscular dystrophy by inhibiting fibrosis and limiting fatty replacement of muscle, thus improving skeletal muscle repair and preserving cardiac function. Interacting and collaborative studies are proposed to address by what mechanisms muscle fibrosis and fat deposition occur. Project 1 is focused on understanding the pathways and cell types that contribute to inflammation, fibrosis, and fatty deposition. Project 1 will evaluate a number of potential therapeutics, utilizing an exciting new mouse model of DMD, the mdx mouse on the DBA background, which may greatly accelerate successful drug translation. Project 2 is focused on identifying and characterizing modifiers of cardiac disease, which in many cases will be modifiers of skeletal muscle disease as well. Project 3 will gain insights into how genetic variations in LTBP4 and Osteopontin impact imaging biomarkers of disease in the heart, respiratory muscles, and leg muscles of DMD patients. In doing so, Project 3 will develop MRI/MRS protocols for monitoring disease progression in the respiratory muscles.